The combat uses for helicopter aircraft have changed dramatically over the years to include contact with opposing forces, including reconnaissance and combat aircraft assistance of troops on the front line. This type of use subjects helicopters to numerous threats, and therefore new helicopter designs incorporate offensive weapons, such as Gatling guns and rocket launchers.
Initially, the primary control of helicopter weapons was accomplished by the pilot aiming the aircraft at the target prior to firing. Correction for misses was accomplished by the pilot adjusting the attitude of the aircraft prior to expending additional ordnance. As technology developed, tracking and sensing systems were used to locate the target and determine the aircraft attitude necessary to aim the weapon so as to account for outside forces acting on the ordnance, e.g., wind, aircraft speed, etc. Such a system typically displays a "cross-hair" indicative of actual aircraft attitude and a geometric shape indicative of the required aircraft attitude to provide a high probability of striking the target with the weapon. The pilot is required to maneuver the aircraft so as to place the cross-hair in the firing solution defined by the shape prior to firing the weapon. The aiming instructions e.g., cross-hair and geometric shape, are typically displayed on a control panel, a heads-up display, or helmet-mounted display which provides the pilot with visual information relating to the target position, ownship attitude, heading, speed and altitude.
Although such aiming systems improved weapons delivery accuracy, the pilot is still under a significant burden to regulate aircraft heading and pitch attitude. It is well-known that a skilled helicopter pilot can control aircraft attitude within about 1 degree of pitch and yaw. Although this may seem very accurate control, a 1 degree variation in pitch or yaw will have a significant effect on the trajectory of a projectile.